Splash-free Urinals… inspired by dogs

To quote from a paper/ design proposal presented at the annual meeting of the American Physical Society’s Division of Fluid Dynamics:

The practice of marking territory with urine is repulsive to most people; ironically, about half of the world's population (males) inadvertently marks bathroom floors, and themselves, through unintentional urinal splash back. This problem has persisted since the invention of the urinal over a century ago. We found that when a liquid jet or droplet train impacts a rigid surface below a certain critical impinging angle, almost no splatter is generated. Thus, a surface designed to always intersect the urine stream equal to or smaller than the critical angle prevents splash back. Inspired by nautilus shells and dog urination, we designed urinal surface geometries that effectively eliminate splatter by satisfying the splash-suppressing intersect criteria.

To quote from one report of the presentation:

It’s unclear whether people using the new urinals will still somehow find a way to make a mess.